Accelerating resonators, in particular super-conductive cavities of particle accelerators, are defined by the construction of the accelerator (cyclotron, linear accelerator and synchrotron) and by the type of particles to be accelerated. The necessity to be supplied with high HF powers is common to all resonators in order to ensure the necessary acceleration field strengths and the desired energy gain of the particles to be accelerated. The transistor-based amplifier modules developed in recent times enable an output power of up to 500 W per amplifier module and in some instances even more than this.
Even in small accelerators, HF powers of considerably more than 10 kW are already required to operate the accelerator and in particular the accelerating resonator. In large cyclotrons or in the accelerating resonators of synchrotrons and storage rings, HF powers of up to 100 kW and more are required. The output power of dozens of amplifier modules (amplifier units) must therefore be collated for operation, i.e. combined or cumulated. For this purpose, the high frequency output signals amplified by the amplifier modules are guided by means of coaxial cables into so-called HF power combiners, which combine the amplified high frequency output signals. Therein, in high frequency technology, a combiner is understood to be an assembly which combines several weaker signals (usually of the same frequency) into a stronger signal. Usually, it simultaneously isolates the inputs from one another, such that these do not mutually influence one another, or the respective other signal generators.
On the one hand, it is problematic that the amplifier units therein, generally, generate considerable waste heat, which must be dissipated. Due to these requirements, the possible design of both the individual high frequency amplifier unit and the entire amplifier system is limited and leads, in the case of high powers, to correspondingly space-filling systems. On the other hand, in addition to this, this procedure becomes increasingly unattractive with increasing frequency of the amplified high frequency output signals to be combined because of the sharply increasing Joule losses in the coaxial cables.
Important requirements for a high frequency amplifier unit having a power combiner are therefore    1. a high economic efficiency (as low as possible investment and operating costs),    2. as low as possible supply line losses (cable) and combination losses and therefore a high efficiency,    3. a compact design and    4. an easy accessibility and exchangeability of the high frequency amplifier units and/or amplifier modules.
The object of the present invention is therefore to provide a high frequency amplifier unit and an amplifier system which fulfils one or all of these requirements.